Expressing fractions with "fenzhi"

分之 (fēnzhī) can be used to form a fraction in Chinese. When expressing a fraction, the denominator is always said before the numerator:

Structure

denominator + 分之 + numerator

So a 1/2 is read 二分之一, not 一分之二.

我们班有三 分之 一的同学是外国人。Wǒmen bān yǒu sān fēn zhī yī de tóngxué shì wàiguó rén.One third of our classmates are foreign students.
我们有二 分之 一的机会成功。Wǒmen yǒu èr fēn zhī yī de jīhuì chénggōng.We have 50 % chance to succeed.
这种事情发生的可能性是万 分之 一。Zhè zhǒng shìqíng fāshēng de kěnéng xìng shì wàn fēn zhī yī.The likelihood of this kind of thing happening is very little.
世界上只有百 分之 三的人能看懂这张图。Shìjiè shàng zhǐyǒu bǎi fēn zhī sān de rén néng kàn dǒng zhè zhāng tú.Only 3 % of the world's population can understand this map.